import java.util.Arrays;

public class demo2 {
    public static void main(String[] args) {
       int[]arr={1,2,3};
       transform(arr);
       //int[]ret=transform(arr);
        System.out.println(Arrays.toString(transform(arr)));
    }
    public static int[] transform(int[]arr){
        int[]tmp=new int[arr.length];
        for (int i = 0; i < arr.length ; i++) {
            tmp[i]=arr[i]*2;

        }
        return tmp;
    }
}
